Side pumped vacuum collar



June 2, 1970 R. P. RIEGERT 3,515,171

SIDE PUMPED VACUUM COLLAR Filed July 23, 1968 I F/G.

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RICHARD P. RIEGERT HIS ATTORNEY States Patent ()1 ifice 3,515,171 Patented June 2, 1970 3,515,171 SIDE PUMPED VACUUM COLLAR Richard P. Riegert, Montecito, Calif., assignor to Sloan Instruments Corporation, Santa Barbara, Calif., a corporation of California Filed July 23, 1968, Ser. No. 746,883 Int. Cl. F04b 37/ 02; F04f 9/00 US. Cl. 137-498 2 Claims ABSTRACT OF THE DISCLOSURE A vacuum system is provided having a side pumped polygonal collar as part of the working chamber.

This invention relates generally to improvements in vacuum equipment and specifically to a feed through collar assembly provided with a side mounted pumping flange.

The usual configuration for a bell jar vacuum system is a mechanical forepump off to one side along with a diffusion pump, gate valve, and cold trap mounted vertically and surmounded by a horizontal, thick metal baseplate which serves as the surface upon which the glass bell jar rests. Feed throughs which transmit electrical or mechanical energy to the interior of the vacuum bell jar are commonly installed in the metal base plate in the area around the pump connection. Space and accessibility are limited by the necessity of having a large pumping port in the base plate with the gate valve, cold trap, and diffusion pump located directly below. Another disadvantage of the vertical arrangement is that small components being processed or tools or parts of fixtures are often dropped into the system plumbing Where they cause damage to the mechanical valves or lower diffusion pump operating efficiency.

In the instant invention a short horizontal pipe joins the diffusion pump inlet to a side flange on a vacuum collar which supports other elements of the working chamber volume. The side flange is provided with symmetrically spaced mounting holes so the collar assembly can be joined to the horizontal pipe in any of several possible positions. The side walls of the collar are preferably made up of relatively thin flat surfaces as hereinafter described.

An object of the invention is to provide a vacuum system having nearly total accessability above and below and around the vacuum collar.

Another object is to provide a vacuum system arranged so that objects cannot be dropped into the pumping station.

An additional object is to provide a vacuum system working chamber which can be extended from a collar in two directions.

A further object is to provide a vacuum system working chamber configuration which may be readily and quickly modified.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following description.

FIG. 1 is a perspective view of a vacuum system with a side mounted collar and a vertical bell jar; and

FIG. 2 is a View, partly in section, showing parts of the vacuum collar and associated elements.

The console 10' of FIG. 1 is provided with the conventional forepump, diffusion pump, bafiles, valves, and pressure measuring equipment. Bell jar 12, enclosed by safety shield 14, rests upon vacuum collar 16 which is joined to the diffusion pump inlet by means of mounting flange 18. Aperturm located in the collar side walls are provided with caps 20' and are available for the insertion of electrical or mechanical feed throughs.

The internal structure of the system of FIG. 1 is shown in FIG. 2 in which parts of the components have been cut away to clarify the assembly. Bell jar 12 is sealed to the top flange 22 of collar 16 by means of boot 24 which is conventionally made of a synthetic elastomer. Bottom plate 26 is sealed to lower flange 28 by means of an O-ring 30 fitted into groove 32. The bottom plate is held securely in place during pump operation by atmospheric pressure; it has been found that four or five clamps 34, of which one is shown, distributed around the periphery of the flange serve to hold the bottom plate in position until a vacuum is drawn. The bottom plate could be bolted to the adjacent flange but the use of clamps permits quick changes and is more eflicient. Flange 18 is provided with bolt holes 36 for mounting purposes. The collar may be rotated so that the bell jar operates in the horizontal position if this is desirable. Since the bottom plate 26 may be changed readily, it is convenient to have a number of plates for each vacuum system and to mount various accessories on these plates. One bottom plate assembly may include an electron beam gun 38 with coolant input tube 40 and output tube 42 as integral components. The electron beam gun can be put into operation by simply connecting leads 44, 46, and 48 to feed throughs 50*, 52, and 54 respectively and providing coolant flow. Substrate holder 56 on post 58 can be designed specifically for use with the associated source. Separate bottom plates provided with thermal evaporation sources or with sputtering units, for example, may be interchanged quickly with any of the other plates. It has also proven feasible to support components directly on the feed throughs; titanium sublimation pumps thus mounted are useful in creating very low pressures. It will be obvious that the vacuum collar 16 can accommodate two bell jars at one time. Alternatively, both ends of the collar can be sealed with flat plates and operations carried out without risk of breaking the glass of conventional bell jars.

The collar may be cylindrical in shape if desired, but it has been found that a folded or polygonal configuration has a number of advantages. The presence of flat surfaces greatly simplifies the mounting of feed throughs. Since the area of each folded face is small compared to the dimensions of a usual base plate it is possible to use lightweight metal therefore. By way of example, a conventional base plate may be one inch thick steel which the fiat faces of the polygonal vacuum collar are amply strong with one-quarter inch thick aluminum.

In operation, the pump station functions in a conventional manner while the accessibility and large useful working volume of the side pumped collar make it possible to process large numbers of parts with dispatch.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. A vacuum system comprising:

(a) a pump station,

(b) a vacuum collar polygonal in section defining part of a working chamber having a plurality of flat side faces and disposed to the side of said pump station, one of said flat side faces having an opening therein, and

(c) pipe means connecting said pump station to the opening defined in the flat face of said vacuum collar.

2. The vacuum system of claim 1 wherein said side pumped vacuum collar defines at least one feedthrough opening in the wall of said collar.

References Cited UNITED STATES PATENTS Ardenne 23069 Milleron 23069 Hablanian et a1. 230101 Abrams et a1. 23069 HENRY F. RADUAZO, Primary Examiner US. Cl. XJR. 

